I used this 0-dust Warlock deck to defeat Heroic Giantfin. The strategy is to try getting every AoE spell (Demonwrath, Hellfire) to control the board, and hang on until you can pull off the Kel'Thuzad bug. It took me several attempts and I BM-fatigued his giant butt in the end.

Used this deck to beat him in normal mode. Took me a few tries, and i replaced Sir Finley of course. In my winning try, i didn't even draw a legendary card, so I basically used the spells to control the board and my way to win was playing the imp gang bosses clever to fill my board with cards, keep my cards at hand low (2-3) to prevent him from drawing too many murlocs.

I think the video was great help and this really is a great budget option.

I just can't say it actually helped me beat this murloc (insert angry word). After 15 or so tries just nope. Whether I get a couple board clears in the opening hand or whether I don't....I just can't win.